In the yawns of wolves, scientists have found a hint of emotional depths once thought restricted to humans and our closest ancestors.

Contagious yawning — the tendency to involuntarily follow suit when seeing another person yawn — is thought to be linked to empathy, drawing on some of the same cognitive mechanisms that underlie our ability to share the feelings of others.

According to a study published, wolves yawn contagiously, too. The results suggest “that basic building blocks of empathy might be present in a wide range of species,” wrote the study’s authors, who were led by cognitive scientists Teresa Romero and Toshikazu Hasegawa of the University of Tokyo.

Yawning itself is a bit of a mystery: Despite many proffered explanations, such as the still-widespread yet empirically unsupported notion that it’s an adaptation for inhaling extra oxygen or expelling carbon dioxide, scientists still don’t know why we do it. They do know, though, that it seems to have a primally social aspect, one drawing on empathy’s neurobiological underpinnings and manifesting in its contagious nature.

The yawns indeed appeared to pass from wolf to wolf; like us, they seemed unable to help themselves. The effect was strongest when wolves could see each other yawning, rather than only hearing it, and was most pronounced between wolves with close social bonds.

That supports an explanation of contagious yawning as helping to “promote social connections and affiliative behaviors among individuals,” wrote the researchers. Put another way, it’s a way of keeping in subtle, long-distance touch with our friends and associates. Yawns were also most contagious among females, supporting the idea that empathy’s evolutionary origins lie in close relationships between mothers and offspring.

“The wolf study indicates that the previous findings in dogs relate to general mammalian empathy,” said de Waal, who was not involved in the study. “Dog yawn contagion is not just there because dogs are domesticated and bred to pay attention to humans. If wolves show the same reactions amongst themselves, this confirms the idea that basic empathy is a mammalian characteristic, found in animals from mice to elephants.”Source